add basic tests for save/restore counting

tests/CanvasTest.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*  Description:
  *      This test defines a series of elementatry test steps that perform
  *      a single or a small group of canvas API calls. Each test step is
@@ skipping 777 matching lines @@
 
     for (int testStep = 0; testStep < testStepArray().count(); testStep++) {
         TestOverrideStateConsistency(reporter, d, testStepArray()[testStep]);
         if (testStepArray()[testStep]->enablePdfTesting()) {
             TestPdfDevice(reporter, d, testStepArray()[testStep]);
         }
     }
 
     test_newraster(reporter);
 }
+
+DEF_TEST(Canvas_SaveState, reporter) {
+    SkCanvas canvas(10, 10);
+    REPORTER_ASSERT(reporter, 1 == canvas.getSaveCount());
+
+    int n = canvas.save();
+    REPORTER_ASSERT(reporter, 1 == n);
+    REPORTER_ASSERT(reporter, 2 == canvas.getSaveCount());
+
+    n = canvas.saveLayer(NULL, NULL);
+    REPORTER_ASSERT(reporter, 2 == n);
+    REPORTER_ASSERT(reporter, 3 == canvas.getSaveCount());
+    
+    canvas.restore();
+    REPORTER_ASSERT(reporter, 2 == canvas.getSaveCount());
+    canvas.restore();
+    REPORTER_ASSERT(reporter, 1 == canvas.getSaveCount());
+}